EP 0548504 B1 19970122 - Process for cleaning silicon mass
Title (en)
Process for cleaning silicon mass
Title (de)
Verfahren zur Reinigung einer Siliziummasse
Title (fr)
Procédé de nettoyage d'une masse de silicium
Publication
Application
Priority
- JP 30826891 A 19911029
- JP 31148491 A 19911031
Abstract (en)
[origin: EP0548504A2] In a process for cleaning a silicon mass with a acid washing solution, a waste solution containing a mixed acid composed of nitric acid and hydrofluoric acid is introduced to a distillation step, and hydrofluoric acid is introduced to a distillation cooling portion to prevent precipitation of silicon dioxide. The waste cleaning liquor is distilled to recover nitric acid. In a process for cleaning a silicon mass by acid-washing with a cleaning solution containing a mixed acid composed of nitric acid and hydrofluoric acid, the cleaned silicon mass is retained in steam of high purity after acid-washing so that acid remaining on the surface of said cleaned silicon mass can be rinsed and removed with condensed water formed on the surface of said silicon mass.
IPC 1-7
IPC 8 full level
H01L 21/304 (2006.01); C30B 33/08 (2006.01); H01L 21/306 (2006.01)
CPC (source: EP KR US)
C30B 33/08 (2013.01 - KR); H01L 21/02046 (2013.01 - EP US); H01L 21/02052 (2013.01 - EP US)
Citation (examination)
- US 4186032 A 19800129 - HAM WILLIAM E [US]
- US 4261791 A 19810414 - SHWARTZMAN STANLEY
Designated contracting state (EPC)
BE DE FR GB IT NL
DOCDB simple family (publication)
EP 0548504 A2 19930630; EP 0548504 A3 19931201; EP 0548504 B1 19970122; DE 69217024 D1 19970306; DE 69217024 T2 19970821; JP H05121390 A 19930518; KR 100230979 B1 19991115; KR 930008193 A 19930521; US 5346557 A 19940913
DOCDB simple family (application)
EP 92118561 A 19921029; DE 69217024 T 19921029; JP 30826891 A 19911029; KR 920020055 A 19921029; US 96706692 A 19921028